JP6088490B2 - MEMS device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a MEMS device and a manufacturing method thereof, and in particular, a device structure and a manufacturing method thereof when forming a wiring structure of a micro device such as a micro sensor by the MEMS device, and further, a micro device using a micro device. The present invention relates to a device structure for forming a path structure or the like and a manufacturing method thereof.

  In recent years, MEMS devices have the advantage of being able to form microstructures with higher aspect ratios (ratio of processing depth / opening width) than semiconductor devices, so physical sensors such as pressure sensors and acceleration sensors, electrostatic force and piezoelectric methods It is widely applied to mechanism devices such as micromirrors and microactuators to which is applied, and fluid devices such as inkjet nozzles.

  These microstructures are processed and manufactured mainly by applying a semiconductor material such as silicon. The processing methods include, for example, an anisotropic wet etching method that forms a structure using the difference in etching rate of the silicon crystal surface, and an RIE (Reactive) of ICP (Induction Coupled Plasma) method that can process grooves with a high aspect ratio. There is a dry etching method using Ion Etching). By processing the MEMS device, it is possible to form a three-dimensional structure and a movable structure made of silicon, and since the processing accuracy is superior to that of machining, it can be applied to various structures.

  Non-Patent Document 1 describes a method of processing by combining a dry etching method and an anisotropic wet etching method. In this document, in order to smoothly process the scallop formed on the side surface of the hole processed by the dry etching method, etching is performed by applying an aqueous solution of potassium hydroxide mixed with isopropyl alcohol (IPA) to reduce the surface roughness of the side surface of the hole. It has improved. A structure to which this method is applied is applied to a mold of a silicon structure.

  In a MEMS fluid device, it is advantageous to agitate and mix liquids if a plurality of silicon nozzles are arranged. In order to form a fine structure such as a silicon nozzle structure, it is preferable that the tip of the through hole has a pore shape. In a conventional structure, a nozzle shape is generally patterned on a flat surface, and a groove is formed by partial etching on a flat surface, which is generally applied in a planar manner. However, in recent years, a three-dimensional structure is also required as a nozzle for an ink jet printer. There exists patent document 1 as a method of manufacturing a through-hole collectively. Patent Document 1 describes a structure in which a multi-stage mask is applied in a dry etching method capable of processing a vertical hole, a vertical hole-shaped opening is formed continuously at the tip of a tapered opening, and a through-hole is provided Describes a method of manufacturing a batch. More specifically, a slope is formed from the opening, and the tip of the hole is vertical.

  In addition, MEMS sensors and actuators can have a movable or sensing function as various sensors and actuators by pulling individual or plural wires from the device substrate. These MEMS structures are mainly divided into electrode substrates for exchanging electrical signals with a device substrate on which a movable part or a sensing part is processed. In some cases, a cap substrate such as a lid is included.

  As a method for pulling out the wiring of the MEMS structure, there are generally a method of pulling out horizontally from the device substrate (lateral direction) and a method of pulling out vertically (vertical direction). Patent Document 2 describes a method in which wiring is drawn vertically, and a through wiring structure is formed at a position away from a structure formed on a device substrate.

JP 2009-44031 A JP 2009-59941 A

J.Micromech.Microeng.13 (2003) S57-S61

  As in Patent Document 1, in a MEMS fluid device, a method of forming a pore nozzle structure at the tip of a through-hole forms a structure having a slope from the substrate surface, and then forms a structure having a vertical hole. It is realized by doing.

  In Patent Document 1, the shape of the through hole is a pore at the tip, but the opening is a sloped hole, and the periphery of the bottom forms a hole composed of a vertical side surface and a planar bottom surface. ing. In this structure, the slope spreads from the opening, and it is difficult to arrange the through holes at a high density, and it is estimated that there is a limit to downsizing the MEMS device. Moreover, since this misalignment or the like occurs in this bonded structure, there is a possibility that the performance may be deteriorated, and miniaturization is increasingly difficult. In addition, it seems to be an acute angle compared to the (111) crystal plane slope of the device structure produced by anisotropic wet etching of silicon, but there are significant differences in shape. It is considered impossible.

  For manufacturing this structure, an anisotropic wet etching method is applied to form a slope, and a structure that is combined with a structure having a vertical hole by bonding is conceivable. For that purpose, the same shape can be processed even if the front side is formed by anisotropic wet etching process such as aqueous potassium hydroxide from the front side and the vertical groove is formed by dry etching process from the back side. It becomes difficult in terms of alignment and continuous processing.

  Further, in Patent Document 1, since the dry etching method is applied to the processing of the slope, there is a concern that it is difficult to control the shape.

  Electrode removal from the device substrate is formed by forming an insulator on the through-hole formed in the electrode substrate from the device substrate on which the movable part or sensing part is formed, and placing an electrical conductor on it. It is advantageous to carry out the method via a lead-out wiring. In particular, a structure with a tapered tip of the through hole can be applied as a structure that pulls out the wiring vertically from the MEMS device, for example, an electrode substrate by performing electrical wiring there, which is advantageous in manufacturing a microstructure. is there.

  The structure in which the electrodes are extracted vertically from the device substrate can be reduced in size because the electrode pads can be disposed on the MEMS device. This structure leads to an increase in the number of chips that can be taken out from a single silicon substrate, and has a cost advantage.

  The method of extracting electrodes vertically from the device substrate is a method of forming a (111) crystal plane slope using anisotropic wet etching of silicon, and forming a wiring along the slope and a dry etching method. There are two methods for forming a wiring by forming a hole and filling the hole with poly-silicon (polysilicon) doped with phosphorus or the like.

  In the anisotropic wet etching of silicon, the dimension formed on the surface of the MEMS device is widened by about 1.4 times the thickness of the electrode substrate. For this reason, an electrode pad that performs electrical exchange with the outside must be formed in a portion other than the opening, and the electrode pad area increases.

  Further, in the structure of the through hole formed by the dry etching method, the limit of the aspect ratio is about 20, and the hole diameter inevitably increases as the substrate becomes thicker. In addition, since there is a limit in embedding all the hole diameters, it is difficult to apply a thick substrate, and there is a concern that processing may be complicated. When the electrode substrate is thin, the device may be deformed by the resin molding pressure in the package process to be finally performed, and the performance may be deteriorated.

  In the electrode substrate, the structure capable of reducing the electrical contact portion with the device substrate leads to the miniaturization of the device from the viewpoint that the area of the movable portion or the sensing portion can be increased.

  Patent Document 2 describes a structure in which the through wiring is drawn out vertically, but the position of the through wiring is arranged outside the device structure, and it is considered that there is a limit to downsizing of the chip.

  Further, even if the wiring structure is formed in the structure of Patent Document 1, it is predicted that there is a limit to downsizing of the MEMS device because the slope extends from the opening.

  Accordingly, an object of the present invention is to provide a structure of a MEMS device having a device structure capable of realizing a wiring structure suitable for miniaturization of the MEMS device, a nozzle structure, and the like, and a manufacturing method thereof.

  The present invention provides a MEMS device having a longitudinal hole, particularly a through-hole, having a structure in which a tip end portion of a longitudinal hole whose side surface extends substantially vertically from an opening is a slope, and a manufacturing method thereof.

  According to an example of the present invention, in order to form a through-hole, a step of arranging a rectangular mask pattern of an arbitrary size on a silicon substrate having a (100) crystal plane in a plane, a high aspect ratio is obtained through the mask. A process of etching a rectangular pattern to an arbitrary depth by dry etching that can be processed, and a process of performing wet etching with an alkaline etchant such as an aqueous solution of potassium hydroxide or aqueous solution of tetramethylammonium hydroxide (TMAH) mixed with isopropyl alcohol A through-hole structure in which a vertical hole whose side surface is perpendicular to the opening is formed by machining including a taper and a hole whose tip is tapered is connected to the vertical hole whose side is vertical. Can provide.

In addition, since the vertical hole of the present invention has a vertical side surface of ( 0 1 1 ) and the crystal surface of the inclined surface of the tip portion is a (111) crystal surface, the angle of the through hole tip portion is The angle is about 54.7 degrees. Although the vertical side surface of the vertical hole is vertical, it may be almost vertical, and the fact that the ( 0 1 1 ) surface of silicon is formed as a vertical side surface by anisotropic etching is used. Therefore, it is sufficient if a substantially vertical vertical hole can be formed. Moreover, the vertical hole of this invention may not be a through-hole, and the utilization as a non-through-hole is also considered.

  Since the nozzle structure having excellent shape accuracy can be obtained by arranging the through holes at a high density, it can be applied to a MEMS nozzle or a MEMS fluid device.

  Furthermore, an insulating film such as an oxide film is formed in the through hole, and an electrical wiring made of a conductive material is formed thereon, so that it can be applied as an electrode substrate of a MEMS device. In the present invention, the through-hole is formed substantially perpendicularly from the opening, and the tip can be formed small, so that the electrical contact with the device structure or the sensing structure can be reduced, thereby contributing to downsizing.

  In the MEMS device of the present invention, since the tip of the tapered portion of the through hole has a small area, it can be easily sealed with a solder material, and sealing is performed while adjusting the pressure in the device substrate. Is possible.

  In addition, since the area around the tapered portion of the through hole is small, it may be formed of a bonding material made of an alloy layer of gold and tin in addition to solder sealing.

  In a structure in which two electrode substrates are stacked and the openings are electrically and structurally connected by bonding, the contact with the device substrate is small, and the dimensions of the electrode pads on the electrode substrate surface Can also be formed small. In addition, the multilayer structure enables the electrode substrate to be formed thick, can sufficiently cope with the pressure at the time of forming the resin package, and does not cause problems such as deformation.

  As described above, the MEMS device of the present invention includes a semiconductor substrate having a first surface and a second surface, and a hole formed in the semiconductor substrate from the first surface, wherein the first surface has an opening. The MEMS device is characterized by using a device structure having a substantially vertical surface and a vertical hole having a small hole diameter as an inclined surface inside, and in particular, the vertical hole is the first The MEMS device is a through-hole extending from the surface to the second surface.

  In addition, the MEMS device manufacturing method of the present invention includes a step of arranging a mask pattern on a semiconductor substrate, and through the mask, etching is performed to an arbitrary depth by dry etching to form a vertical hole whose side surface is substantially vertical. A step of forming a vertical hole, and a step of forming a tapered communication hole surrounded by a slope near the bottom of the vertical hole by performing anisotropic wet etching on the vertical hole, A MEMS device manufacturing method characterized in that a device structure having a vertical hole, particularly a through hole, is accurately manufactured in a semiconductor substrate.

  According to the present invention, it is possible to form a structure in which the tip portion of the through hole is tapered in the MEMS device structure, so that a fine nozzle or the like of the MEMS fluid device can be configured, and a wiring structure is formed in the tapered through hole. Therefore, a MEMS sensor and an actuator having a fine wiring structure can be configured.

  In addition, according to the manufacturing method of the present invention, by performing anisotropic wet etching following dry etching from the main surface of the semiconductor substrate, the tapered hole surrounded by the slope is communicated with the bottom of the vertical hole. Can be produced.

  Thus, according to the present invention, it is possible to provide a MEMS device that can be easily miniaturized and a method for manufacturing the same.

Sectional drawing explaining the through-hole shape of the Example of this invention Detailed sectional view for explaining the shape of the through hole of the embodiment of the present invention Process diagram for explaining the shape of a through hole according to an embodiment of the present invention Sectional drawing explaining the MEMS nozzle device of the Example of this invention Sectional drawing explaining the MEMS device of the Example of this invention Sectional drawing explaining another MEMS device of the Example of this invention Process diagram explaining conventional through-hole shape Sectional drawing explaining the device structure by the conventional anisotropic wet etching method Sectional drawing explaining the device structure by the conventional dry etching method

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the Example described below is a representative example for explaining the embodiment, and the configuration of the present invention is not limited at all by these Examples.

  The shape of the through hole according to the embodiment of the present invention will be described with reference to FIG. 1 and FIG. As shown in FIG. 1, the shape of the through hole 2 formed in the silicon substrate 1 is connected to the bottom surface side while maintaining the vertical shape from the front surface side 1a of the silicon substrate, and is formed to have a taper on the back surface side 1b of the silicon substrate. It has become a shape. In the present invention, the tip end portion of the through hole is tapered, but the opening width of the most advanced portion can be freely controlled depending on the application.

Next, the crystal orientation will be described with reference to FIG. In the silicon substrate, the plane portions 1a and 1b have a (100) crystal orientation, the vertical side surface 2a of the through-hole has a ( 0 1 1 ) crystal orientation, and the slope 2b has a (111) crystal orientation. . Therefore, the angle 3 between the tip of the through hole and the flat portion of the silicon substrate is about 54.7 degrees. In the through hole of the present invention, the vertical side surface is surrounded by the ( 0 1 1 ) crystal plane, and the bottom slope of the through hole is surrounded by the (111) crystal plane. Can be shown. In other words, the through hole shape of the present invention has the following relationship.

(Formula 1)
D2 = (D1 x √2) + D3

Next, the manufacturing process of the through hole will be described with reference to FIG. First, prepare the silicon substrate 1 [Fig. 3 (a)]. Thermal oxide films 4 are formed on both sides of the silicon substrate [FIG. 3 (b)]. After that, the oxide film is removed by the photolithographic process by removing the thermal oxide film only in the opening 5 of the through hole by resist coating, development and exposure [FIG. 3 (c)]. The shape of the opening 5 is preferably a quadrangular shape, and in other shapes, various crystal planes appear on the side surfaces, so that the shape stability is lacking. In this example, a square opening pattern having a side of 50 μm was used.

  Next, a vertical groove 6 is formed by applying a dry etching method using an ICP type RIE apparatus capable of processing a groove with a high aspect ratio [FIG. 3 (d)]. As the dry etching method, the Bosch process method disclosed in Non-Patent Document 1 is suitable. In this Bosch process method, anisotropic etching is performed by alternately repeating dry etching using a gas such as sulfur fluoride-based SF6 and passivation using a gas such as fluorocarbon-based CHF3 or C4F8. is there. In this example, SF6 gas is used in the dry etching process for 7 seconds at a pressure of 3 Pa and a flow rate of 300 sccm, and C4F8 gas is used in the passivation process for 4 seconds at a pressure of 1.4 Pa and a flow rate of 200 sccm. And both processes were carried out alternately for 56 minutes. The substrate temperature was kept at 20 ° C., the main output in the dry etching process was 1000 W, and the bias output was 80 W. The gas species used for dry etching are not limited to those in the above embodiments.

  Finally, anisotropic wet etching is performed by applying a potassium hydroxide aqueous solution in which isopropyl alcohol (IPA) is mixed in a supersaturated state. IPA was supersaturated in 40% by weight KOH aqueous solution, and anisotropic wet etching was performed at 67 ° C. The reason why the IPA is oversaturated is to compensate for the evaporation and decrease of the IPA. By this anisotropic wet etching, the bottom of the hole processed by dry etching forms a slope by anisotropic etching, and the through hole 2 of the present invention can be formed [FIG. 3 (e)].

In an embodiment of the present invention, wet etching is performed by adding isopropyl alcohol to a potassium hydroxide aqueous solution after dry etching. As a result, the ( 0 1 1 ) crystal plane becomes
It utilizes the property that the etching rate is slower than that of the (100) crystal plane.

  The process from FIG. 7 (a) to FIG. 7 (d) is the same as that from FIG. 3 (a) to FIG. 3 (d), but generally no isopropyl alcohol is added as shown in FIG. When the potassium hydroxide aqueous solution is applied, as shown in FIG. 7 (e), the inner surface of the through hole is all covered with the (111) crystal face, and the side surface of the through hole is recessed.

  In the present invention, a fine nozzle device can be manufactured. FIG. 4 is a cross-sectional view illustrating a MEMS nozzle device according to an embodiment of the present invention. FIG. 4 shows an example of an industrial inkjet printer that ejects ink. The ink supplied from the ink tank 16 by the pump 15 is supplied to the ink tank 14, and the vibration of the piezoelectric element 17 causes the ink to pass through the through hole 2 having the shape of the present invention disposed in the nozzle device 13, Ink is ejected from the nozzle device 13 in the ink ejection direction 18. The nozzle device of the present invention can be applied not only for industrial use but also for consumer use.

  More specifically, industrial ink jet printers have a continuous ink jet system in which continuously formed droplets are deflected and used, and solvent-based ink having quick drying properties can be applied to the marking of printed matter. . Arbitrary ink can be marked by combining a charging electrode and a deflection electrode in the configuration of FIG.

  In the nozzle device according to the embodiment of the present invention, the shape of the through-hole 2 is constituted by an etching surface, and the shape can be made finely and with high accuracy.

  Although shown in a sectional view in FIG. 4, it may be arranged three-dimensionally depending on the application. Further, the through holes can be arranged at a high density because they are manufactured by applying the MEMS technology.

In addition, the through-hole structure of the present invention can be applied to mixing or stirring in a MEMS fluid device.
In the present invention, an insulator such as an oxide film can be formed in a through-hole formed in a silicon substrate, and a wiring that can be electrically conducted can be formed thereon, so that it can be applied to a wiring structure of a MEMS device.

  FIG. 5 is a diagram illustrating an example of a sensor device as a MEMS device according to an embodiment of the present invention. The sensor device can be configured by disposing an electrode substrate 19 for performing electrical exchange on a device substrate 7 on which a drive unit or a sensing unit is formed and a cap substrate 8 below.

  The through hole 2 of the present invention is formed in the electrode substrate 19, and the metal wiring 9a and the electrode pad 10 are continuously connected in an arbitrary pattern via the thermal oxide film 4. An arbitrary metal wiring pattern 9b is formed on the back side of the electrode substrate 19. The device substrate 7 is bonded to the electrode substrate 19 and the gap substrate 8 by the bonding layer 11, and the device substrate is sealed in a vacuum or air.

  As an example, the structure 7a of the device substrate is a structure such as a fixed comb of a comb-shaped sensor, and has a structure in which the metal wiring 9a is electrically connected and is connected to the electrode pad 10. The structure 7b of the device substrate is a structure such as a comb for moving the comb sensor, has a structure floating in the air, and can move. Thereby, it is driven when acceleration or angular velocity is applied from the outside, and a change in capacitance with the metal wiring can be grasped. In addition, it can be driven by applying electrostatic force.

  The through hole of the present invention has a slope structure with a tapered tip. Therefore, the metal wiring can be easily formed by a sputtering apparatus or a vapor deposition apparatus. Further, it may be formed by a CVD apparatus or the like. As a result, the wiring can be formed in conformity with the shape without forming the film thick.

  In consideration of adhesion, the metal wiring material may be formed by arranging chromium or titanium as a base film and gold on the base film. Moreover, in order to improve thermal heat resistance, you may arrange | position platinum and nickel between chromium, titanium, and gold | metal | money. The wiring material is not limited to the above, and wiring materials such as aluminum and doped silicon may be applied.

  Also, since the inside of the device substrate is sealed in vacuum or in the atmosphere, the device substrate is sealed by inserting a solder ball into the tip of the through hole and melting the solder ball. Is possible. Furthermore, sealing may be performed using a structure that conducts by bonding.

  As a bonding method between the substrates, eutectic bonding performed by applying eutectic of gold and silicon and gold and tin can be applied.

  The device substrate is preferably a low-resistance silicon substrate, and the silicon material itself can be used as the electrode material. It is also possible to apply an SOI (Silicon on Insulator) substrate to which a cap substrate or an electrode substrate is bonded from the beginning. For example, when an SOI substrate to which an electrode substrate is bonded is used, etching can be stopped with an insulating film (SiO 2 or the like) when a through hole is formed from the surface of the electrode substrate toward the device substrate.

  In the structure shown in FIG. 5, the electrical contact portion with the structure 7a of the device substrate is small, and the electrode pad disposed on the electrode substrate can be made small in that it is drawn out vertically. Therefore, it is possible to reduce the size of the entire device and increase the number of devices that can be taken out from a single wafer, leading to cost reduction.

In the electrode substrate, a structure may be formed in which the peripheral portion of the through hole of the electrode substrate is left and removed by etching, and only the peripheral portion of the through hole is protruded. With this structure, a gap with the device substrate can be easily created. Thereby, a gap for the sensor can be created.
Next, the structural difference between the present invention and the conventional example will be described.

  Next, a conventional wiring lead to which the anisotropic wet etching method of silicon is applied will be described with reference to FIG. The device substrate 7 and the cap substrate 8 in FIG. 8 are the same as the structure in FIG. The electrode substrate 19 is formed with silicon anisotropic etching holes made of inclined surfaces by using anisotropic wet etching of silicon. In this structure, the slope extends from the opening, and the metal wiring can be formed by a sputtering apparatus or a vapor deposition apparatus. The width of the opening portion of the silicon anisotropic etching hole is widely formed because it is about 1.4 times the thickness of the electrode substrate because of the crystal orientation. If the area of the electrode pad is included, the size of the electrode substrate must be further increased, and it is difficult to reduce the size of the electrode lead-out structure using the silicon anisotropic etching hole.

  Further, a conventional technique in which a silicon dry etching method is applied to lead out an electrical signal from a device substrate will be described with reference to FIG. The device substrate 7 and the cap substrate 8 in FIG. 9 are the same as the structure in FIG. The vertical dry etching hole formed in the electrode substrate 19 generally has a structure in which the inside is filled with a conductor portion 20. This is because, even if a metal wiring is to be formed in a high aspect ratio groove, it is broken at the corner of the bottom of the hole. That is, due to the effect of the solid angle, the corner of the hole entrance hinders the inflow of ions during sputtering, making it difficult to form a metal material on the side wall near the hole bottom.

  Even when the inside of the device substrate is adjusted to an arbitrary pressure, since the hole diameter is large in the dry etching hole, it is difficult to seal only with the wiring material. For this reason, usually, the hole formed by dry etching is often filled with a conductor.

  In addition, the dry etching hole has a limitation that the electrode substrate cannot be formed thick due to the aspect ratio. Even if a dry etching method capable of processing at a high aspect ratio is applied, the aspect ratio that can be processed is said to be about 20. That is, even if the hole diameter formed in the electrode substrate is 10 μm, the thickness of the electrode substrate is limited to 200 μm.

  On the other hand, in order to control the sensor structure in the MEMS device, it is connected to the control LSI by wire bonding, and finally packaged with a resin or the like and commercialized. In that case, if the electrode substrate is thin, the sensor may malfunction due to deformation of the resin due to the influence of the external atmosphere after packaging.

  In the present invention, anisotropic wet etching is performed following the formation of holes by dry etching, so that the electrode substrate can be further thickened. In addition, as shown in FIG. 6, the electrode substrate of the present invention can be stacked to form a thicker electrode substrate.

  FIG. 6 is a cross-sectional view illustrating the device structure of a MEMS device according to another embodiment of the present invention. In the embodiment of FIG. 6, the through holes 2 of the electrode substrates 19a and 19b are arranged upside down.

  In the electrical extraction of FIG. 6, the structure 7a of the device substrate 7 is in contact with the metal wiring 9b disposed on the back side of the electrode substrate 19a, and through the metal wiring formed on the side surface of the through hole of the electrode substrate 19a. The metal wiring 9a is formed in the through hole of the electrode substrate 19b. The electrode substrates 9a and 9b are electrically connected by the bonding layer 11, and as a result, it is possible to electrically connect from the device substrate 7 to the electrode pad 10 formed on the surface of the electrode substrate 19b.

  In addition, the area of the electrode pad is reduced at the metal wiring outlet of the electrode substrate 9b, and the entire sensor device can be downsized. Furthermore, it is possible to provide a structure in which the electrode substrate can be formed arbitrarily thick. Thereby, even when the resin is formed, the device portion can be protected from an external force, so that a device with excellent reliability can be provided.

  As described above, in the device structure of the embodiment of FIG. 6, it is possible to obtain an effect of increasing the strength of the MEMS device by forming the electrode substrate thick.

  In the present invention, not only a combination of symmetrical electrode substrates, but also by creating an arbitrary wiring structure on the back side of the electrode substrate 19b, the electrode pad can be drawn to an arbitrary position by extending the wiring. Become.

  The device structure of the present invention shown in the above embodiments can be applied to various MEMS devices, and can be applied to MEMS devices that require electrical exchange such as pressure sensors and micromirrors in addition to fluid devices and sensor devices. it can.

Although the embodiments of the present invention have been described, the present invention is not limited to the above-described examples, and it is easy for those skilled in the art to make various modifications within the scope of the invention described in the claims. Will be understood.

1 ... silicon substrate,
2 ... the through hole of the present invention,
3… An angle at the tip of the through hole,
4 ... thermal oxide film,
5 ... opening,
6… Dry etching groove,
7 ... Device substrate,
8… Cap substrate,
9, 9a, 9b ... metal wiring,
10 ... electrode pad,
11 ... joining layer,
12 ... Silicon anisotropic etching hole,
13… Nozzle device,
14 ... Ink tank,
15 ... pump,
16 ... Ink tank,
17 ... piezoelectric element,
18… Ink ejection direction,
19, 19a, 19b ... electrode substrate,
20… Conductor

Claims (12)

A semiconductor substrate having a first surface and a second surface, and a through hole extending from the first surface to the second surface formed in the semiconductor substrate, the first surface The side surface from the opening of the device is a substantially vertical surface, and the device has a vertical hole in which the hole diameter continuously decreases from the vertical surface inside and becomes a slope, and the side surface of the second surface opens at the slope. Using structure,
A MEMS device, wherein an electrical wiring made of a conductive material is formed in the through hole through an insulating film to form a wiring structure, thereby forming a wiring board.   2. The MEMS device according to claim 1, wherein a device substrate constituting a sensor unit is connected to the wiring substrate, an electrical wiring made of the conductive material is bonded to an electrode of the device substrate, and a signal of the sensor unit of the device substrate is transmitted. A MEMS device which is taken out through the wiring board.   3. The MEMS device according to claim 2, wherein at least two of the wiring boards including the first wiring board and the second wiring board are stacked, and the electric wiring of the first electrode board and the electric power of the second electrode board are provided. A MEMS device, wherein wiring is joined, and a signal of the sensor section of the device substrate is taken out via the first wiring substrate and the second wiring substrate.   The MEMS device according to claim 1, wherein the bottom of the through hole is sealed with solder.   The MEMS device according to claim 1, wherein the bottom peripheral portion of the through hole is formed of a bonding material made of an alloy layer of gold and tin. 6. The MEMS device according to claim 1, wherein the semiconductor substrate is a silicon substrate having the first surface as a (100) plane, and the vertical plane is a ( 0 1 1 ) plane, A MEMS device, wherein the slope is a (111) plane. A semiconductor substrate having a first surface and a second surface, and a through hole extending from the first surface to the second surface formed in the semiconductor substrate, the first surface The side surface from the opening of the second surface is a substantially vertical surface, the hole diameter continuously decreases from the vertical surface in the vicinity of the bottom to form a slope, and the side surface of the second surface opens at the slope, and the slope of the opening Using a device structure having a through-hole having an angle with the second surface of 54.7 degrees,
A MEMS device, wherein an electrical wiring made of a conductive material is formed in the through hole through an insulating film to form a wiring structure, thereby forming a wiring board. 8. The MEMS device according to claim 7, wherein the semiconductor substrate is a silicon substrate having the first surface as a (100) plane, the vertical plane is a ( 0 1 1 ) plane, and the slope near the bottom is (111). A MEMS device characterized by being a surface. (100) A step of disposing a mask pattern on the first surface of a single silicon substrate having a crystal plane as a main surface, and through the mask pattern, etching is performed to an arbitrary depth by dry etching, and the vertical A step of forming a hole, and anisotropic wet etching is performed on the vertical hole, the inside diameter of the hole is continuously reduced from the vertical hole, and the side surface becomes an inclined surface, and the side surface of the second surface is the inclined surface And manufacturing a device structure having a through-hole in the silicon substrate by a vertical hole manufacturing step having a step of forming a communication hole surrounded by a slope in the vicinity of the bottom,
A method of manufacturing a MEMS device, wherein an electrical wiring made of a conductive material is formed in the through hole through an insulating film to form a wiring structure, thereby forming a wiring board.   10. The method of manufacturing a MEMS device according to claim 9, wherein the mask pattern is a square pattern having an arbitrary dimension, and the vertical hole is formed by etching the square pattern to an arbitrary depth by dry etching through the mask pattern. And a process for forming a communication hole surrounded by the inclined surface by etching with an alkaline etching solution in which isopropyl alcohol is mixed with the vertical hole. .   11. The method of manufacturing a MEMS device according to claim 10, wherein the anisotropic wet etching process is a process of performing an etching process using a potassium hydroxide aqueous solution mixed with isopropyl alcohol.   The method for manufacturing a MEMS device according to claim 10, wherein the anisotropic wet etching process is a process of performing an etching process using a potassium hydroxide aqueous solution in which isopropyl alcohol is supersaturated.

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